This invention pertains to electrical circuits, and, in particular, to a method of providing an ultrasound electrical impedance matching circuit which incorporates the use of a computer software program to accomplish this goal.
There have been a number of attempts to design systems to match and evaluate ultrasonic system characteristics. The reason an ultrasound system is such a problem is that the return signal is transmitted over the same coaxial cable as the receive signal. The receive signal is 120 dB down from the transmitted signal. This means that maintaining the lowest possible attenuation during the transmission of the received signal from the acoustic medium of the transducer to the electrical medium of the system controller is imperative. The tuning circuits calculated by the matching software make this goal attainable. This is a desirable goal in order to make the ultrasound system perform more accurately and thereby give better results in its designated uses. What has not been accomplished is a system that will provide the best impedance matching of a transducer to a fixed single ultrasound cable impedance and with different ultrasound system receiver transmitter impedance elements with inductors and capacitors. All components--transducer, cable, rectifier, transmitter--have different impedances and the software will select the electrical matching component to provide the best two way voltage transfer. Another element that has not been accomplished is the design of a system which will select the nearest commercially available components and will display a schematic of the closest matching network circuit. No current systems are available that specialize in medical ultrasound system matching and also allow for the incorporation of characteristic data from a microminature coaxial cable.
Clearly, it is desirable for a method for producing ultrasound electrical impedance matching circuits which is simple to use and, at the same time, be very accurate and effective. It is also a worthwhile purpose to produce a program that will permit the user to use experimental or theoretical data to be selected when inputting parameters from the cable impedance or loss information, from the transducer impedance data, and the system generator and or receiver impedance data. An object of this invention is to provide a method that provides the user with a simple and easy installation of the program with no external pieces in order for it function. It is an object of this invention to set forth an improved method of providing ultrasound electrical impedance tuning circuits thus improving signal to noise ratio, bandwidth and two way voltage transfer which avoids the disadvantages, limitations, above-recited, obtained from other circuit matching systems.